


Flatmates (And Lizards) Should Know The Worst About Each Otter

by flawedamythyst



Category: Sherlock (TV), Sherlock Holmes & Related Fandoms
Genre: Alien AU, Aliens Being Mean To Humans, Crack, Epic Friendship, Fade-To-Black Torture, Gen, It's Possible That David Icke Was Right All Along
Language: English
Status: Completed
Published: 2015-02-28
Updated: 2015-02-28
Packaged: 2018-03-15 16:27:07
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 6,751
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/3454013
Author URL: https://archiveofourown.org/users/flawedamythyst/pseuds/flawedamythyst
Summary: <blockquote class="userstuff">
              <p>John is an undercover alien agent and it's time for his mission to end, but he can't bring himself to leave Sherlock behind. That turns out to be a mistake.</p>
            </blockquote>





	Flatmates (And Lizards) Should Know The Worst About Each Otter

**Author's Note:**

> I blame this entire fic on Emmyangua, who came up with the idea with me, betaed it, and even provided the title. It's definitely all her fault.

The beep from John's watch was so discreet that Sherlock didn't even look up from his book, but it sent a wave of shock through John. It had been almost five years since his last report and he thought he'd been forgotten about.

“Have you seen my laptop?” he asked Sherlock.

“In your room.”

“Ah,” said John and stood up.

He went upstairs but didn't even glance at his laptop where it lay on his bedside table. Instead, he took a deep breath, settled his shoulders, opened up the secret catch on his watch and pressed the button there.

There was another series of beeps, then the sharp twist in his stomach that preceded a teleportation jump. He shut his eyes and when he opened them, he was in the arrivals room of a mid-class reconnaissance ship.

“Welcome back to civilisation,” said the officer who was waiting for him. She leant in close to inspect John's shell. “God, are they all so ugly? Why is the face so flat?”

Having spent over twenty years in the shell, John found himself vaguely insulted by that but he stifled it. Now was not the time to be getting attached to humanity. They weren't going to be around long, after all. 

“This is a very typical representation of the species, sir.”

The officer made a face. “Turn it off, will you? Not sure I can stand to look at it during the debrief.”

John turned off his shell. Readjusting to his actual body always took a few minutes after such a long time undercover. He rubbed his claws over his muzzle, trying to get used to the feel of scales instead of skin.

“Much better,” said the officer. “Let's go to my office.”

Her office was lit by several heat lamps that John wanted to lounge in front of them and enjoy the warmth on his skin. It had been a very long time since he'd had a proper wallow in light and heat. Even the parts of the planet Earth that the humans thought were unbearably hot and bright were dingy compared to his home world.

“Right,” said the officer. “Well, there's not really much to go over. Your reports were very thorough.”

“Thank you, sir,” said John.

“Really, we just need to know if anything substantial has changed since the last one. Any sudden military breakthroughs? I know you were unable to remain in their armed forces after your injury, but presumably you've been keeping up-to-date on any developments.”

“Yes, sir,” said John. “I've closely monitored all their research programs. There's no technology down there that would cause us any problems. They have very little space capability at all, and still haven't managed to get beyond their moon.”

“Excellent!” said the officer. “The rest of the fleet are right behind us, so we'll be able to start the slaughter in just a few rotations.”

“That's good news, sir,” said John, because it was expected of him. The truth was that he always found this part of a mission the most difficult. Going to new worlds and becoming absorbed into their cultures was always fascinating, it was just a shame that it had to end with the wholesale destruction of the population.

“And your anatomical information was so precise that we've been able to put together a few abattoir machines that will completely automate the process,” said the officer. “We expect to be able to get through the entire population in less than one of their solar orbits.”

Within a year, every human that John had ever met would be processed meat. Every single human he had ever glanced at in the street, or seen a photo of, or vaguely heard about on the news. 

“Has there been any discussion of keeping the planet as a farming colony?” he asked, without much hope. He always tried to recommend that step in his reports, but it was very rare for High Command to consider that step. At the very least, it required a much higher reproduction rate than humans were capable of, with guaranteed multiple births.

The officer shook her head. “Not really. I think someone did a cost analysis but it just wasn't worth it, in terms of the personnel it would require long term. Besides, we really need the food now. There's been a major breakthrough in the campaign for the Hjknl-Vmndp Nebula, and the fleet there desperately needs supplies. This planet will keep them fed for long enough to press the advance right into the heart of the Otter Empire's territory.”

John nodded. He understood the importance of keeping the fleet fed so that they could continue the war with the otters that had been raging for generations. That was his main role as a Supplies Reconnaissance Agent. He'd never really had a problem with it before, not when the alternative was their soldiers starving to death, but for some unknown reason the idea of the Earth being slaughtered was making him feel sick.

He was lying to himself. He knew the precise reason why. It was because of Sherlock. He felt vague sadness that the other humans he'd known were going to die, but he could reconcile it with the truth that every species consumed others, plant or animal, in order to survive. The idea of Sherlock becoming food, however, was enough to make his stomach turn. He couldn't remember ever getting as attached to one of the species he had investigated before. There had to be something he could do.

He cleared his throat. “I wonder, sir, if I might ask a favour.”

The officer smiled at him. “Of course,” she said. “We've been very pleased with your work on this one, you know, and you've been with the division a long time.”

John braced himself for the inevitable ridicule. “May I bring one of the Earthlings on board? I intend to keep him as a pet.”

The officer's eyes widened. “A pet? One of those?”

“Agent Dktfs kept one of the Hrthlnks as a pet,” John pointed out. He'd thought the idea frankly weird at the time, especially given how long it took Dktfs to housetrain it.

“Well, yes,” agreed the officer. “But they were at least aesthetically pleasing, with the horns and the shiny eyes. The humans are hideous.”

John couldn't argue with that, other than with a half-hearted shrug. “I've grown accustomed to them.”

The officer let out a little sigh. “Well, I suppose you deserve a reward for your work on this one,” she said. “And one more or less out of seven billion won't really matter. Go and pick it up now and then get back on board. We're only waiting in orbit until the slaughter begins.”

“Thank you, sir,” said John. “I appreciate it.”

The officer dismissed him with a nod and he hurried back to the arrivals room. “I'm just going back down for a few minutes,” he told the transport engineer, who gave him an uninterested nod. She waited just long enough for John to re-engage his shell before activating the teleportation device.

John landed back in his bedroom. He headed for the door, throwing it open in his rush to get to Sherlock and get him off the planet before the humans started being slaughtered.

He started in shock to find Sherlock stood just the other side of the door, so close that he must have been barely inches from the wood.

“Oh, there you are,” said John. “We need to-”

“No,” said Sherlock, taking two steps away so that he was out of John's reach. “I don't think _we_ need to do anything.”

“What?” asked John.

“Teleportation devices leave a very distinctive vibration in the air,” said Sherlock. “Not to mention the noise.”

John couldn't help but stare. “What?” he repeated, this time in a bit of a croak. What did Sherlock, a mere human, know about teleportation devices?

There was the shimmer of a shell being turned off around Sherlock's body and a moment later there was an otter stood in his place.

John had never been on the front lines, and so had never seen one of his ancient hereditary enemies in the flesh before. It was shorter than he'd have expected for a species that had slaughtered so many lizards over the centuries, shorter than the human shell he was wearing by about a foot. 

Beady black eyes stared at him with malice and John started back a step, both with shock and a sudden burst of fear. “What the- How are you-?”

“I could ask you the same thing,” said the otter, thumping his tail against the floor with agitation. “It appears we're both extremely good at blending in, Lizard.”

“But why are you on this planet at all?” asked John. “What can the Otter Empire possibly want with this backwards place?”

The otter twitched his whiskers. John couldn't bring himself to think of it as Sherlock, not now it was clear that everything he had thought he'd known about Sherlock was a lie. 

“You can't possibly think I'll tell you that until you're secure,” he said.

“Secure?” asked John, taking a careful step back and wondering if he should just escape right now. All he needed to do was hit his teleportation button, but then he'd never find out what was going on. “Wh-”

The otter pulled a gun out and shot John square in the chest with a dart. John had enough time to identify it as a tranquilliser specifically designed for Lizard physiology and regret not teleporting when he'd had his chance, then everything went black.

****

When he woke up, he was tied to a chair in a prison cell that was much more advanced than anything a human could create. His shell had been turned off and his watch was smashed on a table in front of him. So much for any chance of getting away.

An otter was watching him from the corner. It took John a few minutes of squinting to ascertain that it wasn't the otter he'd known as Sherlock. He didn't meant to sound speciest, but all otters looked alike to him.

“If you're properly awake, we'll begin,” said the otter.

John recognised the cadence of his speech, even if his voice was different without a shell on. “Mycroft?”

“That is my human alias, yes,” said Mycroft. He glanced down at a clipboard. “Doctor John Hamish Watson. You've been here for twenty Earth years. You studied medicine, gaining detailed knowledge of human anatomy, and then you joined the military, presumably to gather intelligence on human weapons and battle tactics. Classic behaviour for a lizard agent researching the viability of a slaughter.”

“If you say so,” said John, desperately casting his mind back to his training on how to withstand interrogation. The more he remembered, the more obvious it was his position was just about as bad as it could be. No one knew where he was, or even that he'd been taken. No one other than him even knew there were otter agents present on this planet.

“And then today,” continued Mycroft, “after five years of lying low without any obvious intelligence-gathering activities, you teleported from your bedroom, presumably to a reconnaissance ship. A strong indication that the slaughter has been scheduled to begin. I have only two questions for you. When is the fleet due to arrive, and how large is it going to be?”

“You can't possibly think I'll give you military information,” said John.

Mycroft shrugged. “I don't think you'll give it to me easily,” he said. “But I have several methods of persuasion open to me.”

He glanced at a tray next to him, which John could see was covered with a variety of worrying implements.

Great. Torture. He really should have just abandoned Sherlock to his fate and just stayed on the ship. This was where compassion got you.

“I still don't understand what your lot are doing here,” he said, hoping to put off the inevitable. “Two otter agents on a planet that offers nothing of interest to you seems a bit of a waste.” The Otter Empire didn't organise slaughters in order to feed their troops, they put the burden on their vassal planets instead, demanding extortionate food levies from the populace until they were the ones at risk of starvation while their troops all ate like kings.

“Not just two agents,” said Mycroft. “Sherlock and I are merely the ones within the UK. Every country on this planet has agents within it, watching over the human's affairs and making sure things progress the way we want them to. This is the Empress's favourite pleasure planet. She has a great fondness for humans and their antics. We're here to make sure that it's all kept just as she wants it, which I suppose makes us something like zoo-keepers. Or perhaps wildlife rangers.”

John blinked with surprise. “Zoo-keepers?” he repeated. “Wait, you're meant to be keeping this planet in check? You're not doing a very good job - the whole place is ablaze with wars and famines and so on.”

“That's on purpose,” said Mycroft. “The Empress enjoys a bit of excitement. If everything was peaceful and the humans had no difficulties to deal with, what interest would there be to an observer? My role within the government is to manipulate events to ensure there is always an amusing diversion for her. For example, I am directly responsible for the war you fought in.”

“You create wars for a bit of light entertainment?” said John, thinking of the destruction he'd seen in Afghanistan. “That's pretty fucking cold.”

Mycroft looked down his muzzle at him. “This from someone who would be responsible for the eradication of the entire species if we allowed it to continue unchecked.”

“That's different,” said John. “We need the food.”

Mycroft shrugged. “If you ask a human about to be killed if it matters whether they're dying for food or for entertainment, I doubt they'd have a strong opinion either way. At any rate, this is irrelevant. I require information about your fleet.”

“I won't give it to you,” said John, hoping that would remain true.

Mycroft smiled and held up a scalpel. “Let's just see, shall we?”

****

John blanked out as much of what followed as possible. He managed to succeed in not telling Mycroft anything worth knowing, although he rather thought from the way Mycroft went about it that he didn't really expect John to. In many ways, they were just going through the same tired motions of violence and hatred that otters and lizards had been going through for eons.

Eventually, Mycroft gave up and left John alone, and John took the opportunity to quietly pass out.

When he came to, there was another otter watching him. He wondered if they were taking it in turns to practice their voyeurism of unconscious lizards.

“John,” it said quietly, and John realised it was Sherlock. Or, rather, was the otter that had been pretending to be Sherlock.

“Hello,” he said, forcing himself to sit as upright as possible. “Don't suppose you've brought me a cuppa.”

The otter ignored that. “I found myself forced to respect you.”

“Ta,” said John, “but don't strain yourself.”

“You had me completely fooled. You played human impeccably.”

John shrugged. “By the time I met you, I'd been here for fifteen Earth years. I was well-assimilated. And it's not like I had a single clue about you, either.”

The otter dismissed that with a wave of his paw. “I have been here over a hundred Earth years, in one guise or another. I have dedicated my life to understanding and manipulating humans. Of course you wouldn't be able to tell.”

Apparently he was just as arrogant as an otter as he had been as a human. It felt oddly reassuring that some of Sherlock's traits hadn't been acts, although it did open up a realm of questions as to just how much of the person John had known still existed within the otter in front of him.

“I still don't get what you're doing here,” said John. “So, your Empress likes watching humans blow each other up and starve each other to death. How does that fit with a consulting detective?”

“She doesn't just like exciting events on a large scale,” said the otter, stepping towards John with a tilt to his head that John recognised as Sherlock's monologuing pose. “She also enjoys smaller scale stories, particularly crimes. I provide those for her when she drops in for some recreation, and I also send her regular reports for her to enjoy when she has a moment between political engagements.” He cleared his throat. “I must confess that lately, I have just been forwarding her your blog entries.”

John winced. “God, I hope my superiors don't find out I've been writing bedtime stories for the Otter Empress.”

“I don't think you need to worry much about what they think of you now.”

A cold feeling ran through John's limbs. “Yeah,” he acknowledged tiredly. Enemy agents captured by one side or the other only had one fate once the interrogation was over: Execution.

The otter was also silent for a moment. John wondered if he'd grown just as fond of John as the other way around and was regretting that it was going to end with a firing squad. That was probably just wishful thinking, but if John was about to die, he'd prefer to die thinking that the person he'd known as Sherlock actually gave a damn rather than knowing he meant nothing to him.

“There's just one thing I don't understand,” said Sherlock. John couldn't pretend that this otter was completely different and separate from Sherlock, not when he was clearly just as ruled by his curiosity as the man John had counted as a friend.

John sighed. “I'm not going to tell you about our fleet.” Was Sherlock playing the 'good cop' to Mycroft's 'sadistic cop'?

Sherlock made a face that eloquently expressed how little he cared about that. “Of course you won't. You're a good little soldier. That much was obvious about you from the start. We don't need you to tell us, anyway. You lizards are all about _procedure_ after all, and we know exactly what your usual protocol is for a slaughter of this size. Your reconnaissance ship arrived yesterday and the rest of the fleet will be close behind. It will be mostly made up of poorly-armed factory and warehouse ships, with a handful of fighters for protection. They won't be expecting any trouble at all: you clearly had no idea we were here. Our fleet will easily wipe them out once we launch the ambush. That's not really important.”

John glared at him. “Mycroft clearly felt it was,” he said, feeling every single one of his wounds.

Sherlock shrugged. “Mycroft gets bored. No, my only real question is this: why did you come back?”

Ah. Of course he'd have noticed the stupidity of that. “What do you mean?” asked John, hoping that if he played for time, a better answer than 'because I cared too much about you' would occur to him.

Sherlock fixed him with a look that was instantly recognisable despite the change from human to otter. It said _Stop playing stupid, I know you're better than that_ and John had seen it many, many times before. He was hit by a wave of affection that was completely inappropriate given their current circumstances. 

“Your mission was over and you were back with your people. Why did you bother returning to the flat?”

John flicked his tongue out over the scales around his mouth, considering. Could he come up with a believable excuse? Did he really need to bother? If he was about to be executed, what did it matter if Sherlock knew just how much of a sentimental idiot he was? It wasn't as if otters had a very high opinion of lizards at the best of times.

“I came back for you.”

Sherlock started. “What?”

John gave a little shrug, then winced as it pulled at his wounds. “Well, for Sherlock Holmes anyway, who apparently doesn't exist. I didn't want to leave him to be slaughtered with the rest of the humans, so I came back to collect him.”

“And do what with him?” asked Sherlock. “What possible use could a lizard have for a human, other than eating it?”

“I've got a bit of time off owed to me,” said John. “I was going to head home; I've got a house and a bit of land on a world that we slaughtered a few centuries ago, one with a climate much more suited to lizards. I thought Sherlock might appreciate getting to see an alien world.”

“You thought he'd like seeing an alien world with the creature that just destroyed his entire species?” asked Sherlock sceptically.

“Yeah, fair enough,” said John with a sigh. “It wasn't the best plan ever. I just didn't want him to die.” He looked away, not really interested in seeing Sherlock's cold intelligence glittering in beady otter eyes. “We were friends.”

There was a silence, during which John waited to be mocked. Instead, Sherlock let out a long, slow breath. “Yes,” he agreed. “We were.”

John looked over and met his eyes, and managed a weak smile. “Who knew a lizard and an otter could be friends?”

Sherlock let out a dry laugh. “It does seem rather far-fetched.”

“At least this makes sense of why you hated Doctor Who so much,” added John.

Sherlock rolled his eyes. “Whereas now it makes even less sense that you insisted on watching it every week.”

“Are you kidding?” said John. “It's hilarious. The way humans think intergalactic empires and space travel and alien species actually work: it's like a surrealist comedy. Plus, you know. Madame Vastra was hot.”

Sherlock snorted. “She was a human wearing a _rubber mask_ , John.”

“I have an imagination,” said John with a lascivious grin.

“Clearly,” muttered Sherlock.

There was a bleeping noise from outside and Sherlock glanced away. “I need to go.”

“Right,” said John, the temporary bubble of amusement bursting. “Well, I guess this is goodbye, then. Any idea when they'll execute me?”

Sherlock looked back at him with an unreadable look. “Not until after the battle. Once your fleet is annihilated, there won't be any further use for you.”

John nodded. He wasn't sure how long he'd been unconscious, but the fleet couldn't be far away and the battle wouldn't take very long if it was going to be the decimation that Sherlock had predicted.

Less than a day to live, and he was going to spend it tied to a chair in an otter prison cell. If he could have his choice, where would he rather spend it? Strangely, it wasn't his home on another planet that he pictured but 221B, with Sherlock hunched over his chemistry set muttering to himself.

Sherlock headed for the cell door, but paused before leaving. “Were you really coming back to get me?”

John let out a tired sigh. “Yeah,” he said. “Pretty stupid, right?”

Sherlock didn't reply. He left the cell and the lock clicked shut. John settled back to wait for the execution squad to come for him.

****

When the door next opened, several hours later, it wasn't an execution squad. It was Sherlock again.

“If you're here to find out where I hid your cigarettes before I die, you're wasting your time,” said John. “I'm taking that secret to my grave.”

“Don't be ridiculous, John,” said Sherlock. “They're inside your copy of _Disorders Of the Lung_ , in the chapter on lung cancer because you think you're funny.”

“I am funny,” said John. If he was going to die, then he was going to do it with all his illusions about himself intact, damn it.

“Keep your voice down,” said Sherlock, glancing over his shoulder. He crossed over to behind John's chair and started untying him.

“What are you doing?” asked John.

“Getting you out of here,” said Sherlock. “But we have to be quick. Everyone is distracted by the battle, but your fleet is pitiful. It won't last long and you need to be far away by then.”

“What?” asked John, as his bonds fell to the floor.

“Honestly, John, catch up,” said Sherlock. “I'm rescuing you. Let's go.”

John struggled to his claws, trying to massage blood back into his aching limbs. “I don't understand.”

“Ah, your catchphrase,” said Sherlock. “I suppose that alone should have told me that you were a lizard. You're not a species very quick on the uptake, are you?”

“Seriously, Sherlock, what are you doing?” asked John, ignoring the insults. “If I get out, they'll know it was you. And where will I go? To the fleet that's being destroyed?”

“Of course not,” said Sherlock. “You'll have the whole Earth to hide on. I've got your shell, so you can just become John Watson and disappear. Only myself and Mycroft know the identity of the lizard agent we captured and no one will be looking for you anyway, not once we tell them that you died of your injuries.”

John frowned. “I don't understand. Why are you and Mycroft helping me? We're sworn enemies!”

Sherlock gave him a long look and then his ears twitched. “We're friends,” he said, in a soft voice.

John was completely taken aback. For a moment he couldn't find any words to say. “Yeah,” he managed in the end, clearing his throat. “Yeah, we are.”

They held their gaze for a heartbeat, and then Sherlock spun away to glance out of the door at the corridor, checking the coast was clear. “And Mycroft is helping you because I bribed him,” he added. “He's taking all the credit for unmasking you and preventing the slaughter of the Empress's little toys. He's getting a commendation out of it and probably a promotion off-planet, which is what he's wanted for decades. He hates this place.” He gestured at John impatiently. “Come on.”

John followed him as quietly as he could, claws clacking on the metal floor. His head was reeling, and anticipation and relief were fighting in his stomach, making him feel rather light-headed.

They crept along a few corridors to a reception room, where Sherlock gestured at the teleportation device. “Get on.”

“My shell,” John reminded him. There was no way he was going to be able to hide anywhere on Earth while being a six-foot bipedal lizard with a luxuriant scarlet crest.

“Yes, yes,” muttered Sherlock, as if he hadn't completely forgotten. He handed a new watch to John which he slipped on and activated the shell, feeling the familiar form of John Watson shaping around him.

“Right, where do you want to be set down?” asked Sherlock, moving to the teleportation controls. “It's probably best that you stay away from London, just in case Mycroft doesn't stay bribed. From the whole of Britain, really.”

“Oh, right. Yes,” said John. That made complete sense, even if it did strike a pang to his heart. _Better than being executed_ , he thought. “Might take the chance to go somewhere with a better climate then,” he said. “Australia?”

“A land peopled by convicts,” said Sherlock, working the controls. “How appropriate. Right, stand by-”

“Wait!” hissed John. “Sherlock, I- Will I see you again?”

Sherlock paused to look at him. “Possibly,” he said. “I don't intend to leave Earth for a good while yet. My enjoyment of the cases isn't at all feigned, you know. I expect we'll run into each other again at some point.”

 _At some point._ John took a deep breath and nodded. “Yeah, okay,” he said. Probably for the best. John Watson and Sherlock Holmes may have been good enough friends for the affection to have got them this far, but there was no way a lizard and an otter could be friends, not now they both knew the truth. “Well, right then. Thank you, for everything.”

“Yes,” said Sherlock. “I- Yes. John, I will miss you, you know.”

He was staring at the controls when he said it, so John didn't have to worry about the expression that crossed his face in response.

“Yeah,” he said. “Me too.”

Sherlock looked up to meet his gaze, and gave a little nod. “Goodbye,” he said, and a second later John felt the twist of teleportation in his stomach. He shut his eyes.

****

Australia wasn't even close to hot enough for John, but it was a damn sight better than London. He spent several months there, wandering aimlessly about the country. He let people think he was neck-deep in a mid-life crisis that manifested itself in a year's sabbatical from work, a bead necklace and an earnest look in his eyes when he talked about 'casting off the shackles of capitalism'. Every so often, he walked far enough into the desert to be completely isolated, turned his shell off and basked in the sun, wishing for the hotter rays of home.

Mostly though, he missed Sherlock. And not just Sherlock, but the life they had shared, bickering over tea and solving murders. He wasn't even sure any more how much of it had been real, but he couldn't seem to stop picturing a drizzly grey afternoon while the sun was beating down, or thinking he'd seen Sherlock on the street, sprinting down an alleyway after a criminal.

He decided that Australia just wasn't distracting enough and headed to the Atacama desert instead, and then decided to go on a desert-themed tour of the world. Somehow, even in places where he couldn't even begin to picture Sherlock, given how he felt about his massive woollen coat, he was still all John could think about.

He wondered, as he basked on the balcony of his hotel room in Death Valley, why he wasn't missing more about his actual home than just the rays of the star it had orbited around. His job as an undercover agent meant that any connections to family or friends he had once had were long since forgotten about, but surely there should be some sadness that he'd never again return home? It seemed unlikely that he would ever see another lizard, unless they decided that this planet was worth a battle with the otters. John didn't think that very likely when there were so many other inhabited alien worlds around, most of them ripe for a slaughter.

He went to the Sahara and almost got caught up in armed conflict. He wondered if the Otter Empress was being sufficiently amused by the refugees flooding out of the region, all looking shattered and hollow-eyed. How much had her agents had to do to coax the violence into life?

Of course, if the lizards had won the battle, everyone in the region would likely be dead by now. Perhaps what the real question was what the planet would be like if neither the lizards nor the otters had got their claws into it. What would human society be like, left to its own devices?

He stopped at a refugee camp for a few months and worked there as a doctor before drifting on, wondering which desert he should head to next. He considered the relative merits of the Gobi and the Arabian but somehow, when he was at the airport, he found himself buying a ticket for London instead.

Well, it had been nearly a year, and it wasn't as if he had to go to 221B. He could just have a look at a few places and then fly out again. Heathrow was one of the best hubs for international travel.

London was raining when he arrived. He tipped his head back and breathed the damp in, and then got in a taxi, unable to resist the familiar black shape.

“Where to, mate?” asked the cabbie.

John hesitated. He should ask for a hotel. Or a train station that would take him off to another city and out of danger. Or just anywhere other than, “Baker Street, please.”

The cabbie gave him a broad smile that he probably gave every passenger who was about to rack up an enormous fare. “Sounds good.”

He pulled away and John tapped his head against the window, wondering what he was doing. What did he think was going to happen? Sherlock may have rescued him from death, but that didn't change the truth about who they were. Now they each knew the other's secret, how could they be friends? After millennia of intergalactic war, how could any otter and lizard be friends? There was too much history.

John couldn't bring himself to direct the cabbie to 221B so he got out at the tube station. He stood outside it for a while as crowds of people flooded past: tourists headed to Madame Tussaud's, locals just trying to get home, crowds of others than John couldn't identify but that Sherlock would have known every detail about. He tried to convince himself that he was going to head down the escalators and get a Tube to somewhere safer but in the end, when his feet started moving, they headed up the road.

 _This is a terrible idea_ , he thought, but it was too late. He couldn't stop himself now.

Speedy's hadn't changed. Even the posters in the window looked the same. John stood outside and stared up at the first floor windows, wondering if Sherlock was in. Should he just go in? Would it be better if he knocked? Really, he probably should have called ahead – no - texted. Sherlock preferred to text.

“John.”

John spun to see Sherlock standing behind him, holding a Tesco bag and looking surprised in a way John had never seen before.

John's heart thumped in his chest. “Hi,” he said, rather lamely.

Sherlock stared for a bit longer before he moved towards the door. “Come up.”

John followed him upstairs to their flat, where it felt like nothing had changed, even though there seemed to be an entirely new top layer of junk in place of the old one.

Sherlock dumped the bag on the kitchen table and turned to look at John. “If I'd known you were coming back, I wouldn't have bothered doing the shopping,” he said. “You were always much more suited to it.”

“Almost anyone would be more suited to it than you,” said John. “Did you remember milk this time?”

“Why would I buy milk when there's always plenty in Mrs. Hudson's fridge?” asked Sherlock.

John rolled his eyes. “Why the hell hasn't she thrown you out yet?”

Sherlock had stopped paying attention. His eyes flickered over John, no doubt noting every detail. John felt himself straighten and had to fight not to go into parade rest.

“You've been in three different deserts,” said Sherlock. “How predictable for a lizard.”

John cleared his throat. “Four,” he corrected, apologetically.

Sherlock scowled. “There's always something.” He spread his arms wide and nodded at John. “Your turn.”

John let out a half-laugh. “Oh right, yeah. Hang on, let me just become a genius of observation.”

Sherlock tutted. “It's _easy_ if you would just _try_ -”

“Fine,” said John. “You've been in...no deserts. Just London.”

Sherlock dropped his arms. “You missed Paris,” he said. “And a variety of country villages, largely in Sussex. For some reason, everyone in Sussex is just desperate to murder each other.”

“How blood-thirsty of them,” said John.

Sherlock snorted. “Says the lizard who nearly caused the extinction of-”

“Yeah, okay,” interrupted John. “No need to dwell.”

There was an awkward pause. John wondered if he'd made a horrible mistake coming here. As easy as it was to fall back into their old patterns, the tension underneath it was very different.

“I should go,” he said.

“No,” said Sherlock. “Not yet. Stay for tea.”

“You don't have any milk,” John pointed out.

“We'll steal Mrs. Hudson's,” said Sherlock. “You enjoy criminal activity as long as it's relatively mild, and for the greater good.”

“The greater good of tea?”

“Precisely,” said Sherlock. “Come on, John. I promise not to mention the wholesale slaughter of the entire human race.”

John couldn't bring himself to leave, not when Sherlock was all but begging. “Yes, fine,” he said. “But we're not going to steal the milk, you're going to ask for it nicely. With manners.”

Sherlock made a face. “Dull,” he muttered, but when he went downstairs, John could hear him asking Mrs. Hudson with far more courtesy than he had ever shown John.

Sitting in his old chair while Sherlock sat opposite with a mug of English tea made properly was so nostalgic that for a moment John thought he was going to get unpleasantly emotional over the whole thing. Luckily, the moment passed once Sherlock started insulting his intelligence.

They talked of a variety of things. Sherlock caught John up on the London gossip, which largely seemed to revolve around dead bodies and crime scenes. About the only thing that seemed to have changed was that Mycroft had been given a promotion and left the planet within a week of John arriving in Australia.

“His replacement isn't nearly as clever,” Sherlock said. “I foresee an unexpectedly dull period of British political history. The Empress will be disappointed.”

“But the British people will probably be relieved,” said John. “Do you know how many soldiers died in Afghanistan?”

Sherlock raised an eyebrow at him. “If I'm not allowed to mention genocide...”

“Fine,” said John. “Tell me how our friends have been, then. How's Molly?”

They finished their tea and kept talking. It was several hours later when John realised it was getting dark.

“I need to find a place to stay,” he said, looking outside.

“What? Why?” asked Sherlock. “There's a room here.”

John paused. “Sherlock,” he said slowly. “That's not a good idea.”

“It's an excellent idea,” said Sherlock. “It's just as you left it.”

“No,” said John. “Me staying here, us getting close again. It's not – we shouldn't let ourselves fall back into old patterns.”

Sherlock looked at him for a long moment. “You're worried that the enmity between our species will cause difficulties between us. You don't think we'll be able to regain the full depth of our previous friendship now that neither of us is playing a role.”

John shrugged a shoulder. “Lizards and otters aren't capable of being friends.”

Sherlock clenched his jaw and stood up, striding to the windows. He stared at for a moment, during which John thought about getting up and going, but couldn't quite bring himself to. Just a few minutes longer.

Sherlock turned around with a violent movement. “You said I hadn't been to a desert,” he said.

John stared at him. “Uh yeah,” he said. “Seemed safe enough, unless there's a secret one in Sussex-”

“You were wrong,” interrupted Sherlock. “I have been in a metaphorical desert. I have been in this city, playing this role, for a very long time, John. Decades. My name changes but everything else stays the same. Until you moved in. I am loathe to use analogies, John, they are inexact and usually useless, but having once experienced a friendship like ours, being without it was exactly like a desert.”

John stared at him, not sure what to do with all this sudden sentiment from a man who had always professed to hate the very idea of it. But then, he wasn't a man. He was an otter, and he was showing John his true self. 

Perhaps John should do the same.

“Yeah,” he said quietly, thinking about how empty he had felt, even when surrounded by a city full of people. “Yeah, I think I know what you mean.”

Sherlock nodded. “Then there is no sense in letting it continue,” he said. He turned back to the window and pulled the curtains sharply across, then did the same at the other one. He turned back to John and deactivated his shell, shimmering back into an otter. “I'm Sherlock Holmes,” he said. “I'm an otter. Potential flatmates should know the worst about each other.”

John let out a laugh. “That's not even close to the worst about you,” he said. He let out a breath, and then stood up and deactivated his own shell. “I'm John Watson,” he said. “I'm a lizard. I'd like to take the room upstairs.”


End file.
